Dr. Waqas Nawaz
PMAS arid agriculture university rawalpindi
Size: 2.23 MB
Language: en
Added: Nov 26, 2012
Slides: 20 pages
Slide Content
BYBY
General Points Of SkinGeneral Points Of Skin
Layers Of SkinLayers Of Skin
•Skin is composed of 3 layers
1)Epidermis
2)Dermis
3)Hypodermis or Subcutis
EpidermisEpidermis
•Outermost layer of skin
•Derived from basal membrane Stratum Basale
•Presents the openings of hair follicles
•Epidermis consists of 4 sublayers
1.Stratum Corneum – Outermost Horny Layer
2.Stratum Lucidum – Clear Layer
3.Stratum Granulosum – Granular Layer
4.Stratum Spinosum – Prickly Cell Layer
DermisDermis
•Supports the Epidermis
•Consists of Collagen,Reticular & Elastic fibers
•Modify the structure & function of Epidermis
Play role in
•Strength & Elasticity of skin
•Maintenance & Repair of skin
Hypodermis/SubcutisHypodermis/Subcutis
Consists of
•Connective tissue
•Elastic fibers
•Fat - when fat forms a layer of considerable
thickness,it is termed as Peniculus Adiposus
Act as
•Energy Reserve
•Insulator
•Body Contour
More subcutaneous tissue = Skin is raised
Less subcutaneous tissue = Skin is adherent to
subjacent structures
Fat Cells
Functions Of SkinFunctions Of Skin
•Preservation of the animal's shape
•Protection against water loss
•Protection from physical, chemical & microbial
injury imposed by external agents
•Thermoregulation
•Vitamin D synthesis(with the help of sunlight)
҉The protective function of the skin is enhanced by
the presence of sebum & sweat that spread over the
cells of the stratum corneum
Comparative Points Of SkinComparative Points Of Skin
ThicknessThickness
Greater than that of
any other
domesticated animal
Cutaneous GlandsCutaneous Glands
Larger than that of
any other
domesticated animal